In the past, signaling points deployed in the North American Signaling System 7 (SS7) networks were owned and operated by traditional (now often referred to as "incumbent") service providers such as Bell Canada in Canada and American Telephone and Telegraph in the United States. Each SS7 network was therefore, a closed system and its integrity was maintained by the respective service providers who used tight procedural controls and access to information about the network's operation to ensure its security. Deregulation of the telecommunications industry is now forcing more open access to the SS7 networks.
The impetus for the present invention results from the evolving and increasingly liberalized access to SS7 networks. An additional impetus results from the growth and evolution of existing, and future potential SS7 dependent services. Some SS7 dependent services will require service mediation due to the existence of service interworking incompatabilities.
For more than a decade parts of the North American telephone networks have been open to competition. As a result, the networks of new service providers have introduced additional network-to-network interconnection requirements. This exposes the SS7 networks of both the incumbent as well as the new service providers to new risks, despite the fact that network access is still tightly controlled and inter-operating telephone companies sign agreements and follow procedures to preserve the integrity of the networks. Nonetheless, to ensure the stability and integrity of the networks, defensive measures were developed. For example, the SS7 protocol and signaling point behavior were enhanced with Gateway Screening functions to block data packets from entering an SS7 network if they did not conform to a predefined format and content.
Particularly during the last several years, there has also been a substantial growth in the type and number of SS7 dependent services offered to the service subscriber community, including: CLASS.SM., ISDN, AIN, IN, 800, LIDB, PCS, Cellular Mobile, and Local Number portability. Due to adverse feature interactions associated with some of these services, "active" mediation, which includes service prioritization, may be required when a user subscribes to multiple services.
The telephone industry is now looking to further increase openness to its networks, including the SS7 network, for reasons mandated by both government and commerce. As broad access to each SS7 network is increased, however, concern about preserving the integrity of that network escalates because of the fact that the network is integral to the provision of telecommunications services. In order to allay these concerns, business and engineering agreements may be used to define the parameters for SS7 network inter-operation between two service providers. Management of those agreements can be most effectively supported through automated procedures referred to as "mediated access". In addition, the telephone industry is actively seeking to address its growing concern with SS7 service interworking. The management of service interworking procedures can also be supported through the same automated mediation procedures.
Co-pending patent application Ser. No. 08/833,986 filed 11 Apr. 1997 and entitled Method and System for Providing Mediated Access Between Signalling Networks describes a functionally expanded and network centralized embodiment of mediated access called a Signaling Mediation Point (SMP). The SMP is conceived as a new Network Element "dedicated to providing a mediation function". Developing an SMP is relatively difficult, costly, and time-consuming. Besides, the SMP is a new network element which is yet to be proven in the network.
Therefore, a need exists for a mediation access point which is more familiar to the SS7 user community and yet overcomes problems associated with the prior art.